import type { WeekNumberSystem } from '../core/types';
export interface GridCell {
    date: Date;
    inMonth: boolean;
    isToday: boolean;
    dayOfMonth: number;
    weekNum?: number;
    /** 0=Sun...6=Sat (native JS) */
    weekday: number;
}
export interface GridRow {
    cells: GridCell[];
    weekNum?: number;
}
export interface CalendarGrid {
    rows: GridRow[];
    /** Flat list of all 42 cells */
    cells: GridCell[];
    /** First and last visible date (for onOpen range) */
    firstDate: Date;
    lastDate: Date;
    year: number;
    month: number;
}
/**
 * Build a 6-row × 7-col calendar grid for the given year+month.
 * Always 42 cells; cells outside the month have inMonth=false.
 *
 * @param year    full year (e.g. 2026)
 * @param month   0-based month index
 * @param firstDay  first day of week: 0=Sun, 1=Mon, …, 6=Sat
 * @param weekNumSystem  'iso' | 'us' (only relevant when caller requests weekNums)
 */
export declare function buildGrid(year: number, month: number, firstDay?: 0 | 1 | 2 | 3 | 4 | 5 | 6, weekNumSystem?: WeekNumberSystem): CalendarGrid;